Julius alexander nicolaj rasmussen and charles benton hart



No. 62l,l36. Patented Mar. l4, I899. J. A. N. 8. U. B. H. RASMUSSEN.

nmvme GEAR FORJBICYGLES.

(Application filed Mar. 14, 1898.)

(No Model.)

m: cams PETERS 0a.. Pgmrmuwo WASHINGTON. a. c.

JULIUS ALEXANDER NIOOLAJ RASMUSSEN AND CHARLES BENTON HART RASMUSSEN, OF COPENHAGEN, DENMARK.

DRIVING-GEAR FOR BICYCLES.

SPECIFICATION forming part of Letters Patent No. 621,136, dated March 14, 1899.

Application filed March 14, 1898.

To 00% whom it may concern.-

Be it known that we, J ULIUs ALEXANDER NIooLAJ RASMUSSEN and CHARLES BENTON HART RASMUSSEN, of Copenhagen, Denmark, have made a certain new and useful Improvement in Driving-Gearing for Bicycles, which improvement is fully set forth in the following specification.

It is well known that in ordinary cycles provided with a chain the latter forms an elastic connection between the crank-axle and the axle of the rear wheel. Being placed on the ends of the axles in question,it will,when suddenly tightened, draw the hind frame of the cycle toward the crank-axle, so that when riding on rough roads, in starting, or in stopping "the cycle the rear part of the frame is constantly vibrating.

Chainless cycles, notwithstanding their obvious advantages in other respects, have the drawback that they do not possess the abovementioned elastic connection. The pedaling will consequently be hard, all roughness of the road will be felt through the pedals by the rider, and the different parts of the drivinggear will be violently strained. The object of the present invention is to obviate this drawback of the chainless cycles by giving them an elastic connection between the crankaxle and the gearing, whereby motion is communicated to the driving-wheel.

In the accompanying drawings, illustrating our invention, Figure 1 shows a portion of the driving gear-wheel; Fig. 2, a section on the line A B, Fig. 1.

Referring to the drawings,the driving-wheel arevolves on the axle, it being, as shown, fixed onto a tempered-steel tube b, which in a suitable manner is secured on the axle c in the longitudinal direction. A double lever c, placed on the axle c, limits the motion by catching into a recess a. in the wheel a. This double lever is kept in position of rest by a forked spring e,which is hooked onto the driving-wheel bya tenon a with a broader head. The pedals being acted upon the long arm of the lever 0' will press upon one prong of the Serial No. 678,814. (No model.)

forked spring,strainin g it,while the short arm of the lever strains the other prong of spring 6. The straining will increase till it has sufficient force to move the gear. During even riding the straining will be constant; but by riding up and down steep hills it will change, and thus offer the elasticity desired.

Owing to the double action of the arm on the spring 6 the resistance of the latter increases so that its highest strain is reached only now and then, but never surpassed, as the arm 0 touches one side of the recess a, and thus directly rotates the wheel. When the pedals are acted upon in the reverse direction, the double arm 0' will press the opposite prong of spring 6.

Having now particularly described and ascertained the nature of our said invention and in what manner the same is to be performed, we declare that what we claim is- 1. In a driving-gear for chainless cycles the combination with the crank-axle of a drivingwheel loose upon said axle, abent open spring connected with the driving-wheel, and an arm or lever secured to the axle, engaging in a recess in the driving-wheel and between the arms of the spring, the rotary movement of said arm or lever tending to force the arms of the spring apart against the tension thereof,

and be limited by contact with the walls of In testimony that we claim the foregoing as,

our invention we have signed our names in presence of two subscribing witnesses.

JULIUS ALEXANDER NIGOLAJ RASMUSSEN, CHARLES BENTON HART RASMUSSEN.

Witnesses:

J. S. BRUNOHMANN, SIGURD CHRISTENSEN. 

